In a typical air handling device suitable for use in heating, ventilating and air conditioning equipment, a number of dampers are typically found to facilitate the control of the airflow through the air handler unit under varying temperature and humidity conditions. In the past, it was not atypical to find that the dampers, when in the closed position, were not sealed, and that a relatively large amount of undesired airflow would be tolerated within the HVAC equipment. However, in the more recent past, the damper blades have been provided with a seal or seals to facilitate the prevention of undesired airflow when in the closed position. This prevention of the undesired airflow has been found to improve the controllability of the air handler units so as to improve the temperature and humidity controlling abilities of the units while at the same time lowering the amount of energy required to provide the desired heating, ventilating or air conditioning effect.
Several factors must be taken into consideration when employing the damper blade seals, however. The successful damper blade seal and damper blade combination must provide ease of manufacture, low initial expense, acceptable longevity in operating life, and high efficiency in performance. Typically, it has been difficult to met these goals, with one or more of the goals being obtained at the expense of the others. In many cases the damper blade is met with a single seal of the wiper type against which the damper blade seats to obtain a seal due to compression between the seal and the blade. In other cases, damper blade seals or damper blades of relatively complex confirmation are provided so that line contact sealing may be made at more than one point. While these damper blade seals are higher performance, they are often more expensive and involve a relatively large number of steps in the manufacture, and consequently drive up the cost of the air handling unit undesirably.
It is therefore an object of the invention to provide a damper blade and damper blade seal combination which provides for high performance sealing efficiency to prevent undesired airflow when the damper blade is in the closed position.
It is another object of the invention to provide such damper blade seal as will provide multiple line sealing engagement between the damper blade and the damper blade seal when in the closed position to reduce susceptibility of the damper blade seal and damper blade combination to undesired airflow during windy or gusty conditions when employed in an air handler unit.
It is another object of the present invention to provide such a damper blade seal and damper blade combination as is inexpensive and easy to manufacture.
It is another object of the invention to provide such a damper blade seal and damper blade combination as will provide suitable longevity of operation in the air handler unit in which it is employed.